Toy assembly kit



May 26, 1970 A. FISCHER 3,513,588

' TOY ASSEMBLY KIT Filed Jan. 9, 1968 p J I J I i 5 Fig.2

Inventor: A r1 0! fisc mk United States Patent Int. Cl. A63h 33/08 US. Cl. 4625 9 Claims ABSTRACT OF THE DISCLOSURE In a toy assembly kit a building block comprises a rigid carrier having an exposed surface, and a coupling projection extending outwardly from this surface. The coupling projection is of polygonal cross-sectional configura- Patented May 26, 1970 In other words, in such applications the coupling projection received in the complementary groove may be slidable therealong, and is prevented from being withdrawn from the groove transversely of the elongation thereof, but the block and coupling projection associated therewith cannot be turned or rotated with reference to the other element in which the groove is provided. Again, in other applications, the coupling projection is so configurated tion and is undercut intermediate the exposed surface of the rigid carrier and a free end face of the coupling projection remote from this exposed surface. The free end face is provided with a transversely extending slot having a depth in the direction towards the exposed surface which is a fraction of the distance between the latter and the free end face.

CROSS REFERENCES TO RELATED APPLICATIONS Related applications include Ser. No. 553,845, filed on May 31, 1966 in the naine of Artur Fischer, and entitled Building Block, and Ser. No. 580,240, filed on Sept. 19, 1966, also in the name of Artur Fischer and entitled Assembly Kit.

BACKGROUND OF THE INVENTION The present invention relates to toy assembly kits in general, and in particular to a structural element or building block used in a toy assembly kit of the type which comprises a plurality of such building blocks provided with at least one undercut elongated groove and/or at least one coupling projection receivable in such groove.

From my aforementioned prior applications building blocks for toy assembly kits are known which are provided in one or more faces with elongated undercut grooves whose cross sectional configuration diverges inwardly from the respective face in which they are formed These blocks are connected to one another and to auxiliary building elements of the toy assembly kit, by means of connecting heads or coupling projections, which may or may not be integral with the building block, and which are configurated in a manner complementary to the crosssection of the grooves. In other words, these coupling projections are also of undercut configuration so that they have a relatively narrow neck portion adjacent to an exposed surface of the building block from which the complementary projection extends, and a wider head portion carried on the neck portion. The head portion is received in the groove of another block to which the coupling projection is to be connected and the narrow neck portion extends outwardly beyond the groove.

Usually, such building blocks and other structural elements of such toy assembly kits are made of synthetic plastic material. Kits of this type have found wide acceptance because they are highly versatile in the erection of working models and of rather accurate replicas of buildings and other structures, and because they appeal to and can be used by children within a relatively wide age range. The versatility of these kits requires that for some applications there must be provided building blocks which, when their coupling projections are received in the groove or grooves of another building block or structural element of the kit, must be non-rotatably secured thereto.

that such rotation of one block with reference to the other to which it is connected is specifically intended and made possible.

The present invention is concerned in particular with blocks having the type of coupling projection which makes rotation of the associated block with reference to other structural element to which the coupling projection is connected, impossible.

Coupling projections of the type which preclude such rotation are of polygonal cross-sectional configuration, usually of quadratic outline. It is in conjunction with this type of coupling projection that the blocks described in my aforementioned copending applications, and in other copending applications filed by me, have been found to be in need of improvement. Specifically it has been determined that children playing with this type of building block, namely the type wherein the coupling projection is of polygonal and more particularly of quadratic crosssectional configuration, will frequently attempt to turn the block with respect to the other structural element to which it is connected by its coupling projection. This may be inadvertent because the child does not realize that such turning movement is impossible because of the particular cross-sectional configuration of the coupling projection. It may also be deliberate. However, regardless of the reason involved, the result has frequently been that the coupling projection broke off. Of course, a very slight turning movement can be absorbed by the elastic material from which the blocks, or at least the coupling projections, are usually made. However, if the turning movement is more than very slight-which it usually isbreaking of the coupling projection will as a rule be unavoidable.

It is therefore an object of the present invention to overcome this problem. More particularly, it is an object of the invention to provide a building block with a coupling projection which is capable of connecting the building block non-rotatably to the groove of another structural element, but which will permit limited turning movement of the two thus-connected elements with reference to one another without sustaining damage.

SUMMARY OF THE INVENTION In accordance with one feature of my invention I provide, in a toy assembly kit of the type including a plurality of connectable structural elements a building block which comprises a rigid carrier having an exposed surface and a coupling projection of polygonal cross-sectional configuration. The coupling projection is provided on the carrier and projects from the exposed surface thereof. The coupling projection in turn has a free end face spaced from the exposed surface and is undercut intermediate the end face and the exposed surface. In its free end face the coupling projection is provided with a transverse slot means which extends inwardly towards the exposed surface and which enables elastic deflection of the material of the coupling projection in the region of the slot, that is substantially to the extent of the depth of the slot, so that when the coupling projection is non-rotatably received in a complementarily undercut groove of another structural element, the provision of this slot enables limited turning movement of the projection in this groove.

As mentioned before, the cross-sectional configuration of the coupling projection is polygonal, and will usually be quadratic. In a coupling projection so configurated the stud will extend diagonally of the quadratic outline of the coupling projection and this enhances elastic deflection of the material of the coupling projection, particularly in the region of the corners thereof. Particularly in the region of those corners which are connected by the diagonally extending slot, this elastic deflection characteristic is enhanced significantly because, owing to the undercut or inwardly tapering cross-section of the coupling projection, the coupling projection will be bisected into two portions in a region corresponding to the depth of the slot. This will become clearer in the subsequent discussion of the specific embodiment.

It is to be understood, however, that the elastic deformability, that is the deflection characteristic which is to be imparted to the coupling projection by the provision of this slot, must not be so great as to permit deflection of the slotted coupling projection to the extent that the latter can be turned in the groove or can be withdrawn from the groove transversely of the elongation of the latter. The deflection is to be only such as to enable limited freedom of turning movement of the coupling projection in an associated complementary groove, so that the coupling projection can withstand accidental attempts to turn it with reference to the groove. It is assumed that the child, when resistance to such turning movement increases will realize his or her error and terminate the attempt to turn the coupling projection. Evidently, the invention cannot guard against damage to the coupling projection if a child sets out deliberately to break the same by turning it with reference to the groove.

To assure that excessive elastic deflection is not possible, it is necessary that the depth of the slot be only a fraction of the length of the coupling projection, that is of the distance between the free end face thereof and the exposed surface of the block. This makes it possible to provide the desired elastic deflection without, however, increasing this particular characteristic to a point where the coupling projection could be actually rotated in the groove or be withdrawn therefrom transversely of the direction of elongation of the groove. Of course, the depth of the groove, will depend upon several factors, which can be readily determined by those skilled in the art, namely primarily upon the inherent elasticity of the material of the coupling projection and the width of the slot.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side-elevational view of a building block incorporating my invention; and

FIG. 2 is a top-plan view of the building block illustrated in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing in detail, it will be seen that reference numeral 1 identifies a building block or rigid carrier which here is assumed to be of quadratic outline. Evidently, the outline of the block 1 may be other than what is illustrated, as is also evident from the various different configurations which have been disclosed in my aforementioned copending applications.

The block 1 is provided with a plurality of undercut elongated grooves 2 Whose cross-sectional configuration is most clearly visible in FIG. 2. At least one exposed surface of the block 1, namely that identified with reference numeral 3 is provided with a stud-shaped coupling projection 4 which extends outwardly beyond the surface 3. This is shown clearly in FIG. 1, and it is to be understood that the coupling projection 4 may be integral with or suitably secured to the block 1.

FIG. 2 illustrates most clearly that the coupling projection 4 in the illustrated embodiment is of quadratic crosssectional configuration and that it is provided in its free end face 6 with a transversely extending channel-shaped slot 7. Because of the undercut configuration of the coupling head 4, that is because the coupling head 4 decreases in cross-sectional configuration in the direction from the free end face 6 to the exposed surface 3, it is bounded by a pyramidal surface 5 (compare FIG. 1) and it will be seen that in accordance with the invention the depth of the slot 7 is such that it extends into the region of this surface 5. The slot 7 extends transversely of the coupling projection 4, and FIG. 2 shows that it should more specifically be identified as extending diagonally connecting to oppositely located edges 10 and 11.

In FIG. 1 I have illustrated in chain lines a structural element In to which the block 1 is assumed to be connected by means of its coupling projection 4. This is done to illustrate more clearly how the connection is effected and also how the invention makes possible limited freedom of turning movement of the coupling projection 4 in the undercut additional groove provided in the member 1a, this additional groove corresponding to the grooves 2 of the block 1, with the mating configuration of the additional groove and projection 4 constituting means for preventing turning movement of the latter in the former. Opposite of the coupling projection 4 engage the side walls bounding the additional groove in member 1a and it will be understood that, if the member 1 is turned forcibly with reference to the member 1a, the corners 8 and 9 of the coupling projection 4 (compare FIG. 2) will be elastically deflected in the direction in which the turning forces are exerted, such deflection being made possible by provision of the slot 7. Because the corners 10 and 11 are connected by the slot 7, they are spaced from one another by a smaller distance than the comers 8 and 9, it being remembered that the corners 10 and 11 are located in a region of the coupling projection where the cross-sectional area of the coupling projection is smaller than the cross-sectional area of the free end face 6 thereof. This is clearly shown in FIG. 2. This smaller distance, or, putting this in another way, the absence of material in the region of the conrers 10 and 11 over the entire depth of the slot 7 further enhances the ability of the material of the coupling projection 4 to be elastically deflected in the region of the corners 10 and 11.

As pointed out before, the depth of the slot 7 will depend upon the various factors which have been mentioned. Generally speaking, however, I have found that good results can be obtained if the depth of the groove of the slot 7 corresponds substantially to one third of the depth of that part of the coupling projection 4 which will engage the wall bounding the additional groove in member 1a. This figure may be smaller, depending upon the width of the slot 7 and upon the inherent elasticity of the material of the coupling projection 4 or it may be somewhat larger. However, it may not be significantly larger because otherwise the elastic deflection would become too great and complete turning of the coupling projection 4 in the additional groove or even withdrawal of the coupling projection from the additional groove tranversely to the elongation of the latter would become possible, and this is to be avoided.

It is to be understood of course that the embodiment illustrated is by way of example only and that the configuration and outline of the coupling projection 4 as well as of the grooves 2, and the additional groove of the members 1, and 1a, and of the slot 7 may be varied in dependence upon specifically set requirements without in any way affecting the central concept of the present invention.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of structural elements, differing from the types described above.

While the invention has been illustrated and described as embodied in a building block, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention.

What is claimed as new and desired to be prot cted by Letters Patent is set forth in appended claims:

1. In a toy assembly kit including a plurality of connectable structural elements, a structural element provided with an undercut groove having an open end; a building block having an exposed surface; and an elastically deflectable stud-shaped coupling projection of polygonal cross-sectional configuration provided on said building block projecting from said surface and having a free end face and a predetermined length intermediate the same and said surface, said coupling projection being undercut complementarily to said groove intermediate said free end face and said exposed surface, said free end face being provided with a transverse channelshaped slot means extending inwardly towards said exposed surface by a fraction of said predetermined length, said coupling projection and groove having means in the form of mating configurations preventing turning of said projection in said groove whereby when said coupling projection is non-rotatably inserted in said undercut groove of structural element in longitudinal direction of such groove through said open end thereof, provision of said slot means enables limited turning movement of said projection in such groove owing to elastic deflection of the material of said coupling projection in the region of said slot means but does not allow withdrawal of said coupling projection from the undercut groove transversely to the elongation of the latter.

2. In a toy assembly kit as defined in claim 1, wherein said coupling projection is integral with said building block.

3. In a toy assembly kit as defined in claim 1, wherein said coupling projection is non-relea s ably connected with said building block.

4. In a toy assembly kit as defined in claim 1, wherein said coupling projection is of quadratic outline and is bounded intermediate said free end face and said exposed surface by a circumferential face composed of two pairs of opposite surface portions, the surface portions of one such pair being adapted to engage side walls bounding said undercut groove in said structural element on insertion of said coupling projection thereinto.

5. In a toy assembly kit as defined in claim 4, wherein said slot means extends diagonally of said coupling projection of quadratic outline.

6. In a toy assembly kit as defined in claim 4, wherein said coupling projection consists of synthetic plastic material.

7. In a toy assembly kit as defined in claim 4, wherein each of said surface portions comprises a first section closer to said free end face and a second section adjoining said first section and being closer to said exposed surface, said first section being adapted to engage said wall of said undercut groove in said structural element, and wherein said slot means extends from said free end face towards said second section.

8. In a toy assembly kit as defined in claim 7, wherein said first section has a predetermined length intermediate the respective second sections and said free end face, and wherein said slot has a depth corresponding to a fraction of said first section predetermined length.

9. In a toy assembly kit as defined in claim 8, wherein the depth of said slot corresponds to substantially onethird of said first section predetermined length.

References Cited UNITED STATES PATENTS 2,907,137 10/1959 Ehrmann 46-25 2,800,743 7/1957 Meehan et al. 4625 3,032,919 5/1962 Amsler 4625 XR 3,076,286 2/1963 Czecholinski 4625 XR 3,148,477 9/1964 Bjorn et al. 4625 XR 3,162,973 12/1964 Christiansen 46-25 FOREIGN PATENTS 54,584 10/ 1949 France.

221,755 9/ 1924 England.

596,752 8/ 1925 France.

F. BARRY SHAY, Primary Examiner 

